Bolt-anchor.



H. w. PLEISTEM BOLT ANCHOR. APPHCATION FILED JULY I7. 1917- Patented Nov; 27/, 191 y.

UNITE %TATE% PATENT @FIQE.

HENRY W. PLEISTER, F WESTFIELD, NEW JERSEY, ASSIGN 015, TO HENRY B. NEWI-IALL.

BOLT-ANCHOR.

Original application filed January 20, 1917, Serial No.

160,416 I have illustrated, described and claimed a ductile anchor having a body portion which gradually increases in thlckness from the outer end to a point intermediate its ends, and from that intermediate point being of substantially uniform thickness to substantially the other end of the anchor it being understood that the expanding screw vocutsits own cooperating threads in the an chor.

In that copending application have also.

described and claimed such a ductile anchor, as previously described, having 1ncl1ned and cylindrical bores provided wlth lnternal mice of substantially the same depth or height located on both the said inclined and cylindrical bores.

My invention relates to bolt anchors.

More particularly my present invention relates to that class of bolt anchors known as anchors, lead anchors and screw anchors, in which the material of the anchor is formed of more or less ductile material such as an alloy of lead, in which a wood screw will cut its own cooperating female threads. Such anchors are used to hold lighter work than are lag shields.

In the present form of anchors the maximum expansion is approximately at the extreme inner end of the anchor. In practice this is often a serious detriment in that the Patented NOV. at, rear.

143,423. Divided and this application filed. July 17,

Serial No. 181,001.

form of anchors. My invention further permits the wood screw to cooperate with the anchor with less effort than with the present forms.

In my present invention I provide the interior of the anchor with longitudinally extending ribs or surfaces which first engage and guide'the screw as it is screwed home. The wood screw outs its own cooperating screw-threads in these ribs or surfaces, and generally, though not necessarily, cuts entirely through the ribs into the body of the anchor.

In my present invention I provide the anchor with a body formed with an axial bore inclined from near one end to a point intermediate the ends of the anchor, and from that point merging into a cylindrical bore, the inclined bore being provided with internal ribs which are preferably of the same height.

My invention further relates to certain details of construction which will be described in the specification and pointed out in the claims.

In the drawings the same reference numerals refer to similar parts in the different figures.

Figure 1 is a longitudinal, vertical section of my present invention;

Fig. 2 is a vertical section of the bolt a11- chor shown in Fig. 1, located within a wall or other support and cooperating with a wood screw;

Fig. 3 is a transverse vertical section, substantially on the line 33 of Fig. 1, looking in the direction of the arrows;

Fig. 4 is a transverse, vertical section, substantially on the line ll of Fig. 1, looking in the direction of the arrows; and

In the illustrative embodiment of my invention, 1, Fig. 1, is an anchor having a collar 2 and tines 3 and 4. This anchor has a body portion 5 provided with an inclined or conical axial bore 6 extending from substantially one end 7 to a point 8, which is the nearest approach to the axis of the anchor, and which is locatedbetween the end and the end 9. From the point 8 the axial bore is cylindrical to the end 9 of the anchor. Of course the particular location of the point 8 may be varied. On the inclined orconical axial bore 6, I form longitudinally extending ribs 10 of substantially the same height throughout their length. The inner ends of the longitudinally extended ribs 10 merge, at the points 8, 8, into the cylindrical unribbedbore 11 of the anchor.

In my present invention, the point 8, where the ribs 10, 10 approach the nearest to the axis, is due to the formation of the body portion 5 rather than to varying the height or depth'of the ribs 10, which is oneof the forms shown in my parent applica tions. These ribs 10 serve to guide the entering wood screw 12 and permit its easy aassage into the anchor, its male threads 13, cutting their own cooperating female threads in the ribs 10, and usually, though not necessarily, in the body 5 of the anchor also.

It is, of course to be understood, that the depth of the screw threads cut by the screw 12, depends upon the relative size of the anchor, the screw, the size of the hole let and the work or load 15. When this anchor is placed in the hole 1 1 of the support 16 its tines 3 and 4, will be expanded, the maximum grip of the anchor in the hole of the support 16 will extend substantially from the points 17, 17 to the points 18, 18, thus giving a long surface of contact and increased frictional hold and distrubuting the maximum grip over a larger area than the old form of lead anchor now on the market.

These old forms employ a uniformly taper tributed over a larger area to prevent any damage to the support.

In Fig. 2 I have shown the work 15 of a v certain thickness held to the face 19 of the support 16. The same size anchor and wood screw 12 will support different thicknesses of work and permit in all cases, the head 20 of the wood screw 12 to be brought up flush with the work without the screw jamming in the anchor in a position where its head 20 cannot be brought up snugly against the work. That the screw does not jam is due to the fact that the point of maximum expansion is extended over a relatively large surface of the anchor, so that the end 21 of the screw 12 can be brought anywhere along the unribbed or plain cylindrical bore 11, or past the end of the anchor, as may be found Copies of this patent may be obtained for necessary to bring the head 20 flush against the work 15 and at the same time obtain the requisite maximum expansion of the anchor. In the old form, where the maximum expansion is at the end of the anchor, at points equivalent to the points 18, 18, the screw would often jam at this point beforeits head could be brought flush with the work,

for purpose of illustration, I have somewhat exaggerated the preferred angle of the. in clined portion of the axial bore.

Having thus described this 1I1VB11t1011'1I1 connection with an illustrative embodiment;

thereof,to the detailsof which I do not desire to be limited, .what is claimed as new and what is desired to secure by Letters Patcut is set forth in the appended claims.

1. An article of manufacture comprising a ductile anchor having a body portion of varying thickness from one, end to. a point.

intermediate its ends and from that point;

being of uniform thickness to the otherend of the anchor, said anchor being provided with an inclined and cylindrical axial. bore and internal ribs mounted only in the inclined axial bore.

2. An article of manufacture comprising a ductile anchor having an internal bore with an inclined ribbed surface reaching its minimum diameter between its ends and merging into a cylindrical unribbedbore.

3. An article of manufacture comprising a ductile anchor having an internal bore with aninclined surface reaching its minimum diameter between its ends and merging into a plain cylindrical bore, and ri s of substantially the same height upon the inclined surface only.

4. An article ofmanufacture comprising a ductile anchor having an'internal bore of different diameters, and ribs upon that portion of the bore of the greatest Qdiameter only.

HENRY W. PLEISTER, [L.s.] Witnesses:

ELIZABETH. J. Rorrr, MARY R. RYAN.

five cents each, by addressing the Commissioner of Patents, Washington, D G. i i 

